MVC how to pass the updated Model back to a controller through an Html.ActionLink

So I have the following view in MVC4:

@model ViewModel

@section Sidebar
{
    <ul style="margin-left:-20px">
        ...
        <li>
           @Html.ActionLink(@menuItem.Name, @menuItem.ActionName, @menuItem.ControllerName, @Model, new { id = @menuItem.Name + "MenuItemId", style = "font-weight: bold;", @class = "loading" })
        </li>
        ...
    </ul>
}

@using (Html.BeginForm())
{
    <article class="widget widgetFullPage" data-role="collapsible" data-collapsed="true">
        <h2 id="Details">GENERAL INFORMATION</h2>
        <table>
            <tr id="Row1" style="background-color: #FFFFFF;">
                <td id="VarOneId" style="padding-bottom: 10px; padding-top: 20px; width: 300px">
                    @Html.TextBoxFor(x => x.VarOne, null, new { style = "width:100px;" })
                </td>
            </tr>
            ...
            ...
            ...
            <tr id="RowX">
                <td>
                    <input value=" " class="nextbutton loading" type="submit" id="NextButton" />
                </td>
            </tr>
        </table>
    </article>
}

The Submit button in the form works just fine, but I also want to pass the updated model (whatever the user has already typed) through the Html.ActionLink to a different controller in the Sidebar section above, when the user clicks on the sidebar link instead of the submit button.

What I have seems to only pass back the Model with data that's initially passed into the View, not the updated values from the page. What would I need to do to get the updated model and pass that back through the ActionLink?